JPH0332590B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ink for marking pens, and its main purpose is to ink for marking pens that have excellent drying resistance and can be used satisfactorily even when the pen tip is exposed to the atmosphere for a long time. To provide ink for

Traditionally, marking pen ink has been used to prevent clogging of the ink flow path of the pen tip, not only when it is stored in a writing instrument, but also when the cap is removed from the writing instrument body and the pen tip is exposed to the atmosphere for a long time. There has been a strong demand for an orgasm that can always flow out smoothly without causing fluid leakage, and that allows for extremely smooth writing, and various measures have been disclosed to meet this demand. That is, regarding marking pen inks whose main component is a low-boiling point solvent such as ethanol, JP-A-54-72118 discloses that alkylamides, JP-A-54-72118, No. 56-166277 discloses amino acid derivatives, JP-A No. 57-28177 discloses glycerin esters, and JP-A No. 58-79067 discloses sorbitan fatty acid esters, but all of them have short drying times. It's short, and you can't close the cap after drying and write after a while, so to speak.
It has drawbacks such as lack of restorability and is not satisfactory.

As a result of intensive research to solve the above problems, the present inventors found that when sucrose monoester is used in marking pen ink, the OH of sucrose monoester molecules that have many OH groups
The group and the OH group in the solvent molecule form a hydrogen bond, suppressing the evaporation of the solvent, and the sucrose monoester contained in the ink forms a thin protective film on the surface of the pen tip. In addition to suppressing evaporation and improving drying resistance, products with added sucrose monoester also have good recovery properties after dry-up, and if 2 to 12 hours have passed, you can write again if there is any solvent left inside the pen. The present invention was completed based on the new knowledge that sucrose monoester has an outstanding effect as an anti-dry-up agent.

The present invention is an ink for marking pens containing an alcohol solvent and/or a glycol solvent, a coloring agent, and a sucrose monoester.

The sucrose monoester used in the ink of the present invention is a monoester of sucrose and an organic acid that is a mixture of one or more of stearic acid, oleic acid, palmitic acid, lauric acid, naphthenic acid, oxic acid, and benzoic acid. Esters or monoesters of sucrose and hydrogenated beef fat fatty acids, tall oil fatty acids, cocoa fatty acids, and soybean oil fatty acids are preferred. Of course, in addition to sucrose monoesters, such as DK Ester F-160 (trade name, sucrose ester manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and DK Ester F-140 (trade name, sucrose ester manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), By using an ink containing sucrose polyesters such as sucrose diesters and sucrose triesters, it is impossible to predict that sucrose polyesters are contained in the ink.

Commercially available products are used for the above sucrose monoester, but the general manufacturing method is described in "Food Additives and Their Raw Materials" published by Chemical Marketing Center.
It is described on pages 177 to 179. The amount of sucrose monoester is 0.1 to 5% by weight, preferably 0.2 to 2% by weight, depending on the desired drying rate and effect on gloss of the handwriting.
It is preferred to use, at such concentrations, other additives,
For example, it does not inhibit the erasing performance of erasing agents used in whiteboard markers. Incidentally, if the sucrose monoester is 0.1% by weight or less,
No effective dry-up prevention effect can be expected, and if the amount exceeds 5% by weight, the film-forming ability of the resin will be inhibited, resulting in a drawback that the handwriting will not be glossy.

The ink for marking pens according to the present invention contains an alcohol-based solvent and/or a glycol-based solvent,
It contains a coloring agent and a sucrose monoester, and is prepared by mixing it with a resin, additives, etc., if necessary.

Examples of alcoholic solvents used in the present invention include lower aliphatic alcohols such as ethanol, isopropanol, normal propanol, isobutanol, and normal butanol, and aromatic alcohols such as benzyl alcohol.

Examples of the glycol solvent used in the ink of the present invention include ethylene glycol, propylene glycol, ethylene glycol, monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, diethylene glycol monobutyl ether, and the like. The above solvents can be used alone or in combination of two or more. Further, due to the nature of the solvent, it may contain a small amount of water, and as a co-solvent, acetone, xylene, ethyl acetate, N-methylpyrrolidone, etc. may be used.

As the coloring agent used in the ink of the present invention, known dyes and pigments can be used. For example, various dyes such as oil colors, spirit colors, and water colors, pigments such as carbon black, titanium oxide, cyanine blue, cyanine green, Lake Red C, and processed pigments such as microrecolor can be used.

Examples of resins that may be used in the ink of the present invention, if necessary, include natural or synthetic resins that are soluble in the above-mentioned solvents, such as cellulose resins, rosin-modified resins, nylon resins, ketone resins, and polyvinyl butyral resins. In addition, additives that may be used in the ink of the present invention include pigment dispersants, surfactants, glycols as erasing agents, alkyl vinyl ethers, liquid paraffin, plasticizers, etc., PH adjusters such as alkanolamines, Examples include preservatives and rust preventives.

Example 1 Ethanol 40 parts Normal butanol 10 parts Methyl cellosolve 30 parts Varifastred #1308 7 parts (manufactured by Orient Chemical Industry Co., Ltd.) Marquid #33 12.5 parts DK ester F-160 0.5 parts (sucrose ester manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Jojo A red felt-tip ink was obtained by mixing and dissolving the mixture. The stability of the ink over time was good. When tested by setting it in a marker container, it did not dry up for 6 hours at 25°C and 60% RH (relative humidity). The handwriting is
It dried in 30 seconds and gave clear red handwriting. Also,
After removing the cap and leaving it for 10 hours, I put the cap back on and left it for 6 hours, and was able to write again.

Comparative Example 1 A red felt tip ink was obtained in the same manner as in Example 1 except that 0.5 part of methyl cellosolve was used in place of 0.5 part of DK ester in Example 1. The obtained product is 25℃, 60%RH
The dry-up time was 20 minutes. Moreover, there was no restorability.

Comparative Example 2 In place of 0.5 part of DK ester in Example 1, 2 parts of Solgen TW-20 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., sorbitan fatty acid ester) was used, and the other aspects were the same as in Example 1. A red felt pen ink was obtained. The obtained product is 25℃, 60%RH
The dry-up time was 30 minutes. Moreover, there was no restorability.

Comparative Example 3 A red felt tip ink was obtained in the same manner as in Example 1 except that 0.5 part of sucrose polyfatty acid ester was used in place of 0.5 part of DK ester in Example 1. The obtained product was heated at 25℃ and 60℃.
Dry-up time at %RH was 60 minutes.

Example 2 Isopropanol 32 parts Ethyl cellosolve 50 parts Oil Blue #603 5 parts (manufactured by Orient Chemical Industry Co., Ltd.) Hirakku #111 12 parts (ketone resin manufactured by Hitachi Chemical Co., Ltd.) Sucrose monobenzoate ester 1 part Mix and dissolve the above formulations After this, a blue felt-tip ink was obtained. The ink had good stability over time, with a dry-up time of 7 hours at 25°C and 60%RH. Handwriting dries in 30 seconds,
A clear blue handwriting was obtained. Remove the cap again
10 hours later, I took the cap again, and 12 hours later, I was able to write again.

Example 3 Green Mill Base 30 parts Solmicus AP-2 62.5 parts (denatured alcohol manufactured by Nippon Kasei Co., Ltd.) Butyl oleate 7 parts DK ester F-140 0.5 parts (sucrose ester manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Mix the above formulations A green whiteboard ink was obtained by dissolving the mixture.

The mill base was prepared by dispersing the following formulation in a ball mill for 24 hours.

Solmics AP-2 79 parts Eslecs BL-1 10 parts (polyvinyl butyral manufactured by Sekisui Chemical Co., Ltd.) Phthalocyanine Green NY 10 parts (manufactured by Toyo Ink Co., Ltd.) Dispersant 1 part The green whiteboard ink obtained as described above is as follows: When tested by setting it in a marker container, it did not dry up for 4 hours at 25°C and 60% RH. The handwriting dried in 15 seconds, resulting in clear green handwriting. The handwriting is erased without leaving any contamination.
I was able to erase it easily. After removing the cap and leaving it for 5 hours, I put the cap back on and left it for 12 hours.
I was able to write again.

Comparative Example 4 A green whiteboard ink was obtained in the same manner as in Example 3 except that 0.5 part of Solmics AP-2 was used in place of 0.5 part of DK ester in Example 3. Dry-up time at 25°C and 60%RH was 5 minutes. Moreover, there was no restorability.

Example 4 Blackmilbase 30 parts Solmicx AP-2 62 parts PEG 400 7 parts (polyethylene glycol manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Sucrose monooleate 1 part The above formulations were mixed and dissolved to form a black whiteboard ink. Obtained.

The mill base was prepared by dispersing the following formulation in a ball mill for 2 hours.

Solmics AP-2 79 parts Ethyl cellulose 10 parts Carbon Black MA-100 10 parts (manufactured by Mitsubishi Chemical Industries, Ltd.) Dispersant 1 part The black whiteboard ink obtained as described above was placed in a marker container and tested. As a result, the dry-up time at 25°C and 60% RH was 5 hours. Also, remove the cap and
After an hour, I took the cap again, and 8 hours later, I was able to write again.

Comparative Example 5 Blackmilbase 40 parts Solmicx AP-1 51 parts Butyl oleate 8 parts Sucrose polyfatty acid ester 1 part The above formulations were mixed and dissolved to obtain a black whiteboard ink.

The mill base was prepared by dispersing the following mixture in a sand mill for 24 hours.

Solmics AP-1 81 parts Carbon Black MA-100 10 parts (manufactured by Mitsubishi Chemical Industries, Ltd.) Denka Butyral 3000-1 8 parts (manufactured by Denki Kagaku Co., Ltd.) Dispersant 1 part Black whiteboard ink obtained as described above When a test was conducted by setting the marker in a marker container, the dry-up time was 10 minutes at 25°C and 60% RH.

Claims (1)

[Scope of Claims] 1. An ink for marking pens containing an alcohol solvent and/or glycol solvent, a coloring agent, and a sucrose monoester. 2 Sucrose monoester content is 0.1 to 5% by weight
The ink for a marking pen according to claim 1.